1. Field of the Invention
The invention relates to a steering system.
2. Description of the Related Art
If a vehicle collides with an obstacle such as another vehicle, subsequent to a primary collision of the vehicle with the obstacle, a secondary collision of a driver with a steering wheel, which is a steering member, may occur. In order to absorb an impact caused by a secondary collision, there have been proposed various configurations for removing part of a steering column from a vehicle body to move the part of the steering column in the axial direction of a column shaft (toward the front of the vehicle body) in a steering system. For example, in a steering column supporting device described in Japanese Patent Application Publication No. 2012-121538 (JP 2012-121538 A), a pair of engagement cutouts extending parallel to the axial direction of a column shaft is formed in a vehicle body-side bracket secured to a vehicle body. One engagement capsule is fitted in each of the engagement cutouts, and each engagement capsule is positioned with respect to the vehicle body-side bracket with a plurality of engaging pins. A column-side bracket that holds a steering wheel is connected to the engagement capsules with bolts.
At the time of a secondary collision, the engaging pins break to remove the engagement capsules from the vehicle body-side bracket, so that the engagement capsules are moved along the engagement cutouts together with the column-side bracket. In this way, an impact caused by the secondary collision is absorbed.
In the steering column supporting device described in JP 2012-121538 A, fragments of the engaging pins that break at the time of the secondary collision may drop from the engagement capsules and the vehicle side bracket. If all the fragments of the engaging pins drop, it is not possible to find the fragments of the engaging pins after the secondary collision. Under such circumstances, it is not possible to clearly determine whether the engaging pins set in advance breaks properly at the time of the secondary collision to fulfill an impact absorbing function, or the engaging pins are actually not present from the beginning because the engagement pins are not set during assembly.